Dynamically Pulling Query Results in FLASK Using Dropdown Selection

Описание: Learn how to dynamically filter DataFrame content in your Flask application based on user selection from a dropdown menu.
---
This video is based on the question https://stackoverflow.com/q/74106490/ asked by the user 'user11740857' ( https://stackoverflow.com/u/11740857/ ) and on the answer https://stackoverflow.com/a/74141991/ provided by the user 'Detlef' ( https://stackoverflow.com/u/13708022/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Dynamically pull query in FLASK

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Dynamically Pulling Query Results in FLASK Using Dropdown Selection

In the world of web applications, interactivity and dynamic content are key to a great user experience. A common requirement is to filter data displayed based on user input. In this guide, we will explore how to dynamically pull query results in your Flask application using a dropdown menu. Our example will demonstrate how to filter a DataFrame based on the selection made by a user.

The Problem: Displaying Filtered Data in Flask

As a newcomer to Flask, one of the challenges you may encounter is displaying only specific rows from a DataFrame based on user input. For instance, if you have a list of names and want the application to display only the selected name's details when chosen from a dropdown menu, how would you implement that?

The Existing Setup

In our simplified application, we start with a DataFrame containing names and age:

[[See Video to Reveal this Text or Code Snippet]]

Currently, the application displays all contents without any filtration based on the user's selection. Let's explore how to change this functionality using Flask and HTML.

The Solution: Dynamic Filtering Based on User Selection

To achieve the desired functionality, we need to modify the Flask application and the HTML template to handle user selection and filter the DataFrame accordingly.

Step 1: Modifying the Flask Application

We'll update our Flask route to handle the filtering based on user selection effectively. Here’s the revised app.py code:

[[See Video to Reveal this Text or Code Snippet]]

In this updated code:

We check if the request method is POST to gather user inputs from the dropdown.

The DataFrame is filtered to include only the rows matching the selected names.

Step 2: Updating the HTML Template

Next, we need to create or update our HTML template to include a dropdown menu that allows selecting the names, as shown below:

[[See Video to Reveal this Text or Code Snippet]]

Key Features of the HTML Template:

A form that uses POST method to submit the selected names.

A dropdown menu (<select>) allows multiple selections.

Data is displayed in a table format, dynamically updating based on user selection.

Conclusion

With the modifications outlined above, your Flask application can now dynamically filter a DataFrame based on user input from a dropdown menu. This adds an interactive layer to your application, enhancing the user experience while allowing for a streamlined presentation of data.

Feel free to adapt the provided code snippets to fit your specific requirements. Happy coding!